> Size: 31551
> TotalSize: -1
> why the TotalSize is -1 ?> there are hundreds files in my grabbing they are
all 
> look like that  
> why ? and how to solve this problem ? 

This is neither a bug, or a problem. The "-1" just 
means "the remote server is just too lazy to give me 
the size of the document I requested, so I will have 
to receive the data and count the amount of bytes by 
myself"

This has no effect, except VERY slight performance 
loss and CPU consumption, say, 0.00001 seconds for 
each request